How should traumatic hemorrhage in a pregnant patient be managed, including maternal resuscitation, fetal monitoring, imaging, hemorrhage control (surgical or interventional), and Rh immunoglobulin administration?

Management of Traumatic Hemorrhage in Pregnancy

Maternal resuscitation takes absolute priority over fetal concerns, as optimal maternal stabilization is the most effective intervention for fetal survival. 1, 2

Immediate Maternal Resuscitation

Airway and Breathing

• Insert a nasogastric tube in any semiconscious or unconscious pregnant trauma patient to prevent aspiration of acidic gastric contents. 1
• Administer supplemental oxygen to maintain maternal oxygen saturation >95%, which ensures adequate fetal oxygenation. 1
• If thoracostomy is required, insert the chest tube 1-2 intercostal spaces higher than standard placement due to diaphragmatic elevation in pregnancy. 1

Circulation and Hemorrhage Control

• Establish two large-bore (14-16 gauge) intravenous lines immediately in any seriously injured pregnant patient. 1
• Begin resuscitation with warmed blood products (packed red blood cells) rather than crystalloids in cases of massive hemorrhage with severe anemia. 3, 4
• Transfuse O-negative blood immediately without waiting for cross-match in Rh-negative mothers to avoid both delays in resuscitation and Rh alloimmunization. 1
• Administer blood products in a 1:1 ratio (4 units packed red blood cells to 4 units fresh frozen plasma) for massive transfusion. 3

Positioning and Hemodynamics

• After 20 weeks gestation, manually displace the gravid uterus to the left or use left lateral tilt to relieve inferior vena cava compression and improve venous return. 1, 2 When using left lateral tilt, secure the spinal cord appropriately if spinal injury is suspected. 1
• Use vasopressors only for intractable hypotension unresponsive to fluid resuscitation, as they adversely affect uteroplacental perfusion. 1
• Do not inflate the abdominal portion of military anti-shock trousers, as this reduces placental perfusion. 1

Coagulopathy Management

• Administer tranexamic acid 1g IV within the first 3 hours of bleeding onset in cases of severe hemorrhage. 3
• Maintain fibrinogen levels >1.5 g/L and platelet count >75 × 10⁹/L. 3
• Actively warm the patient and all transfused fluids to prevent hypothermia-induced coagulopathy, as many coagulation factors function poorly below 36°C. 5, 3

Diagnostic Evaluation

Laboratory Assessment

• Obtain baseline complete blood count, coagulation panel including fibrinogen, blood type and cross-match, and serum lactate (>2 mmol/L indicates shock). 3, 1
• Perform Kleihauer-Betke testing in all Rh-negative pregnant trauma patients to quantify fetomaternal hemorrhage and determine appropriate anti-D immunoglobulin dosing. 1, 2
• Consider point-of-care viscoelastic testing (thromboelastography or thromboelastometry) if available to guide targeted hemostatic therapy. 5, 3

Imaging

• Do not defer or delay medically indicated radiographic studies, including abdominal CT, due to concerns about fetal radiation exposure. 1, 2 The benefit of maternal diagnosis and treatment outweighs theoretical fetal radiation risks.
• Use focused abdominal sonography for trauma (FAST) to detect intraperitoneal bleeding. 1
• Consider abdominal CT as an alternative to diagnostic peritoneal lavage when intra-abdominal bleeding is suspected. 1

Hemorrhage Control Interventions

Surgical Management

• Patients presenting with hemorrhagic shock and an identified bleeding source should undergo immediate surgical bleeding control unless initial resuscitation measures are successful. 5
• Apply damage control surgical principles in severely injured pregnant patients, limiting initial surgery to hemorrhage control and contamination control. 5
• For pelvic ring disruptions: close and stabilize the pelvis, followed by angiographic embolization or surgical packing. 5

Interventional Radiology

• Consider angiographic embolization of hypogastric arteries for uncontrolled pelvic hemorrhage. 3
• Pelvic packing can be left in place for 24 hours with open abdomen and ventilatory support if needed. 3

Fetal Monitoring and Assessment

Timing of Fetal Evaluation

• Fetal assessment should be performed at the end of the primary survey after rapid maternal evaluation and stabilization. 2
• All pregnant trauma patients with viable pregnancies (≥23 weeks) should undergo electronic fetal monitoring for at least 4-6 hours. 1, 2

Extended Monitoring Indications

Admit for 24-hour observation if any of the following are present: 1

• Uterine tenderness or significant abdominal pain
• Vaginal bleeding
• Sustained contractions (>1 per 10 minutes)
• Rupture of membranes
• Atypical or abnormal fetal heart rate pattern
• High-risk mechanism of injury
• Serum fibrinogen <200 mg/dL

Ultrasound Evaluation

• Perform urgent obstetrical ultrasound when gestational age is undetermined and delivery may be needed. 1
• All pregnant trauma patients admitted for monitoring >4 hours should have obstetrical ultrasound prior to discharge. 1
• Defer speculum or digital vaginal examination at or after 23 weeks until placenta previa is excluded by ultrasound. 1

Rh Immunoglobulin Administration

• Administer anti-D immunoglobulin to all Rh-negative pregnant trauma patients regardless of injury severity. 1, 2
• Use Kleihauer-Betke test results to calculate the appropriate dose of anti-D immunoglobulin for massive fetomaternal hemorrhage. 1, 6 Standard dosing is 50 μg for first trimester events and 300 μg for events after 12 weeks, but massive hemorrhage may require doses exceeding 6,000 μg. 6
• Administer the calculated dose within 72 hours of injury, though earlier administration is preferable. 5

Resuscitative Hysterotomy

• Perform emergency cesarean section for viable pregnancies (≥23 weeks) no later than 4 minutes following maternal cardiac arrest to aid maternal resuscitation and fetal salvage. 1, 2 This is termed resuscitative hysterotomy and should be initiated at the bedside without transport to the operating room.

Triage and Transfer Decisions

• Transfer to the trauma unit or emergency room for major injuries regardless of gestational age. 1
• Transfer to the labor and delivery unit when injuries are neither life- nor limb-threatening and the fetus is viable (≥23 weeks). 1
• When injury severity or gestational age is uncertain, evaluate in the trauma unit first to rule out major maternal injuries. 1

Common Pitfalls to Avoid

• Do not focus on the fetus before the mother is properly stabilized—an apparently stable mother may be compensating at the expense of the fetus. 7
• Do not rely on maternal blood pressure alone as an indicator of adequate resuscitation, as pregnant patients can maintain normal blood pressure despite significant blood loss due to increased blood volume. 8, 7
• Do not delay management of suspected placental abruption pending ultrasound confirmation, as ultrasound is not sensitive for this diagnosis. 1
• Do not use excessive crystalloids (>1-2 liters) as primary resuscitation fluid in massive hemorrhage, as this worsens dilutional coagulopathy without restoring oxygen-carrying capacity. 3, 4